Plug connection for pressure systems

Abstract

A plug connection for a pressure system comprising a receptacle part and a plug part, the plug part is inserted into the receptacle part and retained therein by a locking device which forms a prelocked, unsealed connection and a locked, sealed connection between the plug part and the receptacle part with a limit stop element which indicates when the locked, sealed connection has been obtained.

We claim: 
     
       1. A plug connection for pressure systems, comprising: two coupling parts, a receptacle part (2) and a plug part (4) forming a plug shaft (6) and seal means carried by one of said parts;   the plug part (4) being insertable into a receptacle opening (8) of the receptacle part (2) such that the plug shaft (6) is circumferentially sealed by said seal means relative to the receptacle opening and is blocked from being separated by means of a locking device (12);   the locking device (12) comprising at least one elastic holding element (18) arranged in a recess (14) of one coupling part and, in a connected position of the coupling parts, engaging in locking fashion behind an edge (16) of the other coupling part;   a limit stop element (20) arranged between the two coupling parts (2, 4) to apply an axial contact between the coupling parts during insertion of the plug part (4) so as to cause a noticeable increase, during or shortly after the connected position is reached, in the coupling force required for coupling the plug connection;   the limit stop element (20) comprising a ring (24) of elastically deformable material, the ring being arranged in a radial recess or groove (26) of one coupling part and cooperating with a step edge (28) of the other coupling part;   the step edge (28) being arranged between two surface sections (32, 34) that form an obtuse angle >90°; and   a substantially radially extending projection (36) arranged within the recess (26) to engage the limit stop element (20) so as to produce an elastic radial prestress of the limit stop element.   
     
     
       2. Plug connection according to claim 1, characterized in that the limit stop element (20) is in the form of a O-ring with essentially circular cross section. 
     
     
       3. Plug connection according to claim 1, characterized in that the locking device (12) is selectively operable to a completely connected position which corresponds to the connected position as well as a partially connected position that corresponds to a prelocked position, wherein the seal produced by said seal means in the partially connected position is so incomplete that, an acoustically perceivable leakage noise is generated if the plug connection is charged with pressure. 
     
     
       4. Plug connection according to claim 1, characterized in that the limit stop element (20) is arranged within the region between said seal means (10) that functions as the main pressure seal and the end of the receptacle opening (8) on the insertion side. 
     
     
       5. Plug connection according to claim 1, characterized in that, in the connected position, the limit stop element (20) exerts an elastic prestress force upon the plug part (4) in the separating direction and thusly compensates axial play of the plug part.